Exploration of A Seaice Hazard Warning Program For Winter Production in The Bohai Oil Fields

Abstract

Abstract The existing offshore oil/gas fields in production in the Bohai Sea are all confronted with sea ice problems in the cold years. The development of a sea ice state warning system for the winter oil production in these fields is discussed in the paper on the subsidiary topics as: the skeleton of the system, monitoring and forecasting of the sea ice condition and the offshore structural behaviours, the criteria of warnings, and the database and software networks. The system is developed for various types of offshore structures and different oceano-geographical regions in the Bohai Sea. Introduction Several offshore oil/gas fields including Chengbei, BZ28-l, BZ34-2, JZ2O-2 and SZ36-l fields in the Bohai Sea have been put into operation since 1980s, making a total output of 1.3 million tons crude oil and 500 million cube meters natural gas per year. Besides, there are other new fields such as : JZ9-3, Boxi and CFD-16–1 fields still in construction (Figure 1). Various types of offshore structures - jackets, jackup rigs, single point mooring (SPM) systems and artificial islands-are used in these fields, and they all may be standing in the drifting ice in such a cold winter as that in 1969. A drilling jacket and a flare jacket were totally pushed over by ice in 1969 and 1977, respectively. The JZ20-2 jackets were distressed by vibrations resulted from ice in the recent years, which gave influences on the offshore natural gas production and salo on the mind of the people working on board. P. 533